The Koinonian homeworld was an inhabitedplanet. This planet was home to two sentient species, the extinct corporealKoinonian and their non-corporeal neighbors who still inhabited the desolate planet in the 24th century. The planet was classified as M-class, type 4, and was considered only marginal suitable for Human habitation. The radiation factor was measured at 6 and the result of scans for minerals were unreliable, possibly due to the radiation. It had a Freeman radius of 0.017453, a planetary body of K2, a mass of 8.02e24×1024 kilograms, and a circumference of 1.31e4×104 kilometers.

The corporeal Koinonians destroyed their entire race and ravaged the planet in the Koinonian Wars and left behind only dust and rocks on the surface. Some underground caverns, including the ceremonial chamber, and tunnels still remained intact, but the rest of the planet is completely barren.

The USS Enterprise-D did some archeological research on the planet in 2366. During the research, LieutenantMarla Aster was killed by an explosive device, a relic of the Koinonian Wars. Later, the crew of the Enterprise-D learned of the existence of the non-corporal lifeforms through the actions of this species to atone for the death of Aster. (TNG: "The Bonding")